Techniques and Early Results of Treatment of Carcinoma of the Larynx and Pharynx by Supervoltage Radiation

Abstract

The purpose of this paper is to describe the techniques used and to give the early results of treatment of carcinoma of the larynx and pharynx by supervoltage radiation. The type of supervoltage radiation used in the techniques described is that from the 8 MV M.R.C. linear accelerator at Hammersmith. It was in 1948 that the Medical Research Council sanctioned a project for the design and construction of a linear accelerator for the treatment of patients by high-voltage X rays. It took four years work before the machine was installed in the Radiotherapeutic Research Unit at Hammersmith in 1952 and the treatment of patients by 8 MV X rays began in 1953. When treatment first started, it was felt desirable to begin by treating only the more advanced cases, whatever site was being treated. After some months' experience in the use of this type of radiation early cases also were accepted for treatment. Growths in the mouth and throat are situated at no great depth, but seemed very suitable ones to treat because such lesions offer an excellent opportunity for observing the effects of the radiation, not only on the response of tumour and nodes but also on the reactions produced in normal tissues such as skin and mucous membrane. The isodose curves at 8 MV and those at 250 kV are compared in Fig. 1 and the physical advantages of the higher voltage radiation can be clearly seen.